Grinding apparatus



March 8, 1949. 5, cu 2,463,750

GRINDING APPARATUS Filed April 12, 19 16 5 Sheets-Sheet 1 H/Torney March 8, 1949. C 1

GRINDING APPARATUS 5 Sheets-Sheet 2 Filed April 12, 1946 INVENTOR March 8, 1949. U 1 2,463,750

GRINDING APPARATUS Filed April 12, 1946 3 Sheets-Sheet 3 IN VEN TOR:

fimme Patented Mar. 8, 1949 "U N l TED STATES PATENT 2,463,750

GRINDING APPARATUS ,George M. Curtin, Gloversville,-N. Application 12, 1946, SeriaINoxBiiIIIM :1 I This-invention relates to apparatus for grinding material, and particularly strip material, very accurately to a desired thickness. The device is particularly adapted ior the grinding or non-flexible striplnaterial, such for example as strips of mica, plastic and the like.

:It is an object of the invention 'to provide a simple, practical and efllcient apparatus of the above meritioned kind.

Another object of the invention isto provide an apparatus for grinding strips of rigid material which must be ied 'toandthroughthe machine in astraight line.

:An'other object of the invention is to provide simplified means for "adjusting and setting -a de- :vice of theabovem-entioned kind.

:Another object of the invention is to -'provide grinding apparatus "by which the thickness of the product may be controlled to measurements on the order of ten thousandths of an inch.

Another object of the invention isto provide grinding apparatus adapted to reject material which is too thick i or the setting of the machine.

Another object of the invention is to provide grinding apparatus which may be readily set in advanceito grind to the desired thickness, and without the repeated trial gauging operations characteristic of the p'rior ar-t.

Another object of the invention is to provide grinding apparatus in which all the material supporting, pressing, and advancing means' may b'e raised and lowered as a unit.

.Another object of the invention is "to provide .a grinding apparatus in which the direction of rotation of the grinding -roll may be reversed without reversing the direction of rotationof 'the pressure roll, thus making it possible to grind inaiterial with either a climb or a plunge out.

Another object o! the invention is to provide grinding :Japp'aratu's capable of grinding a taper, so that one surtace'of thestrip after *beinggr'ound will be inclined relative to the other, and the product will increase in thickness froinone lateral margin to the other.

Other objects of "the invention will be in part obvious or in part pointed out hereinafter.

The invention -accordinglly consists in the features "of construction, combinations of elements, arrangements of ;in the several steps end-relation and order or zeachof said steps "to 401m. (Cl; -1-78) one 01- more of the'=others thereof, all as "will be pointed out in the following description, and the scope o'f the application of which will be indicated -in thefollowing olaims.

"The' inven tion will best be understood iii the cfo'ilowiing des'crir'ition is tread lin oonn'ection with the drawings in which,

Figure i1 is a diagrammatic side view an the grinding roll and pressure roll 'assemblies of t'he embodiment of the invention shown :in Figure '2;

Figure 2 is a tron't 'elev'ationel view :of the de- 'vicewiththehasingremoved;

Figure 3 is a vertical sectional wiew taken on ith'e line 13-43 (if- Figure 2 looking :in the direction of the arrows;

:Figure 4 is aside 'view looking in the direction of the arrows 4 4, 'Figurefz; "and iFigure :5 11s a frront elevation of the "complete device without "the motor and speed reducer.

machine comprises the base In and the side creme members t! and l'l. lh'e grlnding roll 16 is supported in the frame near the top or the irame =by Bm'ea'n's of its trunnions l8 which are received in bearings 20 and 22 in the frame members l2 and M respectively, 'The grinding sur- Iaceniay be a sheet .ofisa'ndpaper l1, detachably mounted as 'by any suitable clamp means 19 show extending over the ends "of the grinding roll-ft Beneath the grinding 'r'oll an assembly, comprising a "pressure roll 24 which maybe raced with :rubber or the like, material support members "28 and 26', lower fe'ed ro1ls'28 and drive rolls 13b for driving the feed rolls from the pressure roll, is supported-on slide members 32 and 3" which are mounted-in vertical slideways 3B and 38 provided respectively in the opposite irame support-members f2 and '14.

The flower freed rolls n and the drive rolls 30 :are supported on their trunnions 40 and '42 respectively inzbearings provided by end plates "4'4 and 16 respectively which in turn are secured to the slide members 32 'and 34 respectively, as by screws es, and therefore are carried by, and moved in unison with, the said slide members 32 --and 34.

Preferably adiustable swivel bearings 41 and 43, which may be of a known kind as illustrated, fixed'on the end plates and, are provided ior thetrunni'ons In: and M respectively, to per- 1ml. Slight angular adjustments il'l the position 3 of the lower feed rolls, 28, and driving rolls 30 and thus insure operative contact between the driving rolls 30 and the pressure roll 24, and with the lower feed rolls 28, respectively.

The presser roll 24 is provided with trunnions 5B which extend through holes Si in the end plates into bearings 52 in the slide members 32 and 34 respectively.

The material support members, as shown, comprise the front and rear members 26, and the intermediate members 26 the latter being spaced apart and disposed on opposite sides of the presser roll 24 with their top surfaces on a level with the top of the pressure roll, and the members 26 being spacedoutwardly from the members 26 and disposed on the opposite side of the lower feed rolls 28 respectively, from said memv bers 26 in the same horizontal plane as members 26 7 The members 26 are shown mounted on end plates 44 and 46, with their depending flanges 21 secured to the end plates respectively, as by screws. The members 26 are supported from the end plates by means permiting the height of said members, and the angle of the surface of said members, to'be adjusted, and so that the whole members or either the leading or the rear edge of said members 26 may be raised or lowered with respect to the other edge as may be required to properly align said members with respect to each other, the members 26, and the lower feed rolls 28. As illustrated herevin the members 26 are secured to the top of the end plates 44 and 46 respectively by long screws 54 positioned intermediate shorter screws 56 and 58, it being apparent that one edge of members 26 may be elevated with respect to the other by loosening one set of screws 56 and 58, and taking upon the other set of screws 56 or 58.

It will thus be apparent that the pressure roll 24 and its assembly; including the lower feed rolls 28, the feed roll drive rolls 30, and the material supporting members 26*- and 26*, may be raised or lowered with respect to grinding, roll I6 to provide the desired space between the pressure roll and thegrinding roll for the strip ofgmaterial M to be ground to the desired thickness.

Positioned above the path of the material, on shafts B and 62 which extend between the frame members l2 and I4 arethe upper feed rolls 64, which are vertically aligned with the lower feed rolls 28, and form with the feed rolls 28 respectively pairs of feed rolls, adapted to engage the strip of material M both in advance of, and behind the grinding roll, each pair of feed rolls serving to engage the strip of material and to advance it. As will be more fully explained the direction of rotation of the feed rolls may be reversed to cause the material M to be driven in either direction through the device.

The slide members 32 and 34 are supported on shafts 66 and 68, the lower ends of which are threaded and are received respectively in the shoulder bushings I0- and I2, which are fixed for rotation to the worm wheels 14 and I6, which in turn are actuated by the worms I8 and 80, on the hand wheel shafts 82 and 84 respectively, operated by hand wheels 86 and 88..

Oneof the worm gears is righthand and the other is left hand and they may be interconnected for operation in unison by the chain 90 (Figure which may be made to engage sprocket Wheels 92 and 94, respectively on, hand wheel shafts 82 and 84, so that both shafts may be connected through chain and operated simultaneously upon operation of either hand wheel thus causing the slides 32 and 34 and their associated end plates 44 and 46 respectively to be elevated and lowered together and to the same amount.

The hand wheels have calibrated hubs 86 which preferably are calibrated in ten thousandths of an inch 50 that one revolution of either hand wheel 86 or 88 raises the corresponding slide member 32 or 34 .005 of an inch.

By the means described the whole pressure roll assembly may be moved toward or away from the grinding roll I6 extremely gradually, making it possible to grind many materials including rigid strip materials, such for example as mica, to much more exact thicknesses than has heretofore been possible.

Furthermore, by positioning one of the slides 32 or 34 at a different height from the other,

through operation of one or both of the hand wheels while. chain 90 is removed from the sprocket wheels 92 and 940m the hand wheel shafts *82 and 84, with the result that shafts 82 and 84 operate separately, a taper grind may be given to the strip M. Thus the strip may be ground so that it increases in thickness from one lateral margin to the other.

The pressure roll assembly bearing support slide blocks 32 and 34 can be locked in any desired position by means of the locking pins I04 (Figure 3) respectively, which threadedly engage in the shoulder bushings I06 having knobs I01 respectively by which they may be rotated, the inner ends of the pins I04 respectively being movable upon rotation of their respective shoulder bushings into engagement with the metal blocks I88 which are loose within the bores IIO within which the shoulder bushings are received. When either locking pin is moved inwardly it presses against its associate metal block which in turn forces the raised slide block against the opposite side of its slideway, and thus frictionally locks the block in its slideway.

A gauge (Figure 1) is provided for initially adjusting the vertical distance between the grinding roll I6 and the pressure roll assembly, to grind the work strip to the desired thickness. The gauge comprises a calibrated dial I20 having the pointer I22 which is mounted on a shaft I24 controlled by the thumb screw I 26. A gauge rod I28 is connected to the pointer shaft I24, as by a ratchet and pinion connection, not shown, so that vertical movement of the gauge rod swings the pointer. The pointer is first set at zero and the gauge rod is then used to gauge the setting given the apparatus by operation of the hand wheels, and thus a check is obtained as to the thickness which will result from the setting, in advance of any work being done, thus greatly simplifying the operation of setting the device and checking the setting. Heretofore gauging has ordinarily been performed only on strips which have been passed through the apparatus, thus making a succession of gauging operations necessary as a preliminary to the final adjustment of the apparatus and before the working run is begun.

In initially adjusting the machine the hand wheels 88 are operated to elevate the pressure roll assembly until the pressure roll 24 and the grinding roll I6 are brought into contact. When sparking between the grinding roll and the pressure roll ceases the gauge roll I28 is moved down nst, the upper surface. of. the .work support anaemic member 326 and the pointer 122 is set at -zero. The :hand wheels 88 are now operated to lower the pressure roll assembly an amount equal :to the thickness to which the strip of material M is to be ground, and this setting is checked by now again moving the gauge rod 128 down into contact with the top surface of the support plate 26 thus moving pointer IZZ-andcauSingitto indicate the thickness for which the apparatus is set.

A guard member I39 is provided whichis positioned in :advance of the front pair of ,feedzrolls, and means 'are provided to'adjustzit vertically so that it acts also as a selecting device to reject any strips of material which are too thick :for ;the setting of the machine and mightthereforacause jamming and damage to the rolls. Accordingly the guard member is secured to the frame by the adjusting screw I32 extending through 'vertical slot I34, and the lower end :of the guard is adjusted to be approximately the same height above the work support plate member as the bottom of the top feed rolls 64.

The drive is from the motor I49 through pulley I42 on the motor shaft I44, belt I46, and the trunnions I8 of the grinding roll I6 through pulleys I41 and I49, through belt Iii! and pulley I50 on speed reducer shaft I5I, down to the speed reducer I52, and from the speed reducer to the pressure roll 24 through gear I54 on shaft I56, chain I58, and sprocket I68 on the trunnions 50 of the pressure roll. The pressure roll 24 drives the driving rolls which in turn drive the lower feed rolls 28, which, together with the upper feed rolls 64, and the pressure roll, feed the material through the machine.

It will be noted that pulley members I49 and I each comprise two pulleys of different diameter. By changing the belt I48 between the pulleys of pulley members I49 and I50 the speed of drive be modified through the speed reducer means I52, which may be of standard form and so is not described in detail.

Since the direction of rotation of the grinding roll I6 may be reversed with respect to the direction of rotation of the pressure roll assembly either a climb out or a plunge cut may be obtained, if desired, depending upon the direction of rotation of grinding roll I6.

To compensate for adjustment of the pressure roll assembly in a vertical plane, means are provided for tightening chain I58 and thus keeping it firmly engaged at all times on sprockets I54 and I60. As illustrated a 'T-shaped bracket IE2 is pivotally mounted on the machine frame by pivot I64, and on a vertically extending arm of the bracket the sprockets I66 and I58 are rotatably mounted and spaced apart one above the other in engagement with chain I58 on opposite sides. The other or horizontally extending arm of the bracket is connected to the machine frame by the spring I'Ill which tends to pivot the bracket to take up any slack in the chain I58.

The apparatus described herein has the advantage of flexibility in that, because of the unitary mounting of the pressure roll assembly, opposite ends of the assembly may, if desired, be elevated separately and to different elevations, or both ends of the assembly may be moved in unison and by the operation of a single hand wheel. The unitary mounting of the pressure roll assembly makes practical the employment of gauge means as described herein making it possible to speedily obtain the desired setting of the machine, down to a setting of ten thousandths of an inch, and before the start of aa working -:operation, thus eliminating :the feeding, :gaugin'g, and resetting operations characteristic of :the .operation of prior art grinding :machines in preparation for aworkingoperation. The ability of the machine togrind a taper, or to grind withieitheria climb or a plunge cut, as may be desired, .contributes further to the flexibility and versatility of th machine, and the unitary mounting nfzthe pressure roll assembly further cooperates with the guard "means and makes it possible for :the guard means toautomatically reject strips oiim'aterial which are .too thick for the setting of :the machine, by-maintaining thesupport memberslzfi and 26*, the lower feed rolls '28, and 'the pressure roll 24 with theirtops atthesame level and equally spaced from the bottom of the upper feed rolls 64 and the bottom'of the grinding :roll

It will thus be seen that there has been vprovided by this invention a method and apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As various possible embodiments might be made of the mechanical features of the above invention and as the art herein described might be varied in various parts, all without departing from the scope of the invention, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

What I claim is:

1. Grinding apparatus comprising, a frame, a grinding roll rotatably mounted in said frame, a pressure roll rotatably and slideably mounted in said frame for movement toward or away from the grinding roll, material supporting means movable toward or away from the grinding roll in unison with the pressure roll, means supported by said frame and positioned above, and adjustable vertically with respect to said material supporting means to provide clearance between itself and said material supporting means substantially equal to the clearance between the grinding roll and the pressure roll and thus cooperating with the material supporting means to serve both as guard means and work selector means, and means for advancing a strip of material over said material supporting means.

2. Grinding apparatus comprising, support means, a grinding roll, a pressure roll movable toward or away from the grinding roll, both said rolls being rotatably mounted in said support means, material supporting means movable toward or away from the grinding roll in unison with the pressure roll, and means fixed to said support means including a member movable in a vertical plane toward or away from said work supporting means, and. adapted to cooperate with the work supporting means and to be moved from zero position into contact with the work supporting means after the apparatus has been adjusted for a grinding operation to gauge in advance the thickness to which a strip of material will be ground by passing through the apparatus as adjusted.

3. Grinding apparatus comprising, a frame, a grinding roll rotatably mounted in said frame on a fixed axis, upper feed rolls mounted in front and behind-said grinding roll in fixed bearings with their bottoms on a level with the bottom of said grinding wheel, a unit adjustable vertically toward and away from said grinding roll comprising lower feed rolls vertically aligned with said upper feed rolls respectively, a pressure roll, work support counters in front and behind said pressure roll with their upper surfaces respectively on a level with the top of said pressure roll, means for driving the pressure roll, and rolls intermediate the pressure roll and said lower feed rolls respectively by which the drive of the pressure roll is transmitted to said lower feed rolls causing them to rotate in the same direction as the pressure roll.

4. Apparatus for grinding rigid material such as mica, plastic and the like which comprises, a grinding roll, a pressure roll, opposed upper and lower feed rolls in front and behind said grinding roll and said pressure roll, means for positively 15 1,280,639

driving both of said rolls, means for advancing a strip of material by passing it through said pairs of feed rolls, and means for driving the lower feed rolls from the pressure roll consisting of idler rolls intermediate said pressure roll and said 0 lower feed rolls respectively, the said upper feed rolls being driven from said lower feed rolls by contact with the material which is being ground.

GEORGE M. CURTIN.

REFERENCES CITED The following references are of record in he file of this patent:

UNITED STATES PATENTS Number Name Date 238,095 Doane et a1 Feb. 22, 1881 269,729 Simonds Dec. 26, 1882 592,679 Young Oct. 26, 1897 Beier et al. Oct. 8, 1918 2,187,462 Mulholland Jan. 16, 1940 FOREIGN PATENTS Number Country Date 157,459 Germany Dec. 20, 1904 lnfifnfonn lf Certificate of Correction Patent No. 2,463,750 March 8, 1949.

GEORGE M. OURTIN It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows:

Colurnn 3, line 23, after the word screws and before the period insert the letter 3; line 24, same column, for perrmting read permitting; column 4, line 74, for gauge roll read gauge rod;

and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 26th day of July, A. D. 1949.

THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

